textproduct: Rapid City

KEY MESSAGES

-Hot this weekend with highs in the 90s and a few low 100s

-Elevated to critical fire weather conditions this weekend

-Wildfire smoke is expected to linger at through Sunday

-Dry through the weekend most places, the exception will be across south central SD Sat morning and northwest SD Sunday afternoon where there are chances for thunderstorms

-Unsettled and cooler next week

UPDATE

Issued at 942 PM MDT Fri Aug 7 2026

Elevated convection will develop across scentral SD early Sat in response to a LLJ, which will support strong pos theta-e adv. Mean elevated CAPE of 1500-2000 J/kg will support isolated severe thunderstorms with large hail being the main threat. Dry elsewhere tonight. Hot Sat with highs in the 90s and a few 100s on the SD Plains. Breezy in the afternoon across the western third behind a sfc trough, where deep mixing will support gusts over 30 mph in areas. Sfc trough will move through Sat and could support isolated TS across scentral SD in the evening. Very small chance for this. Otherwise, slightly cooler Sunday, but still warm with highs in the 90s. Flow will veer around to the ESE by afternoon. Another impulse may support a slight chance for TS across northwest into central SD Sunday night. Flow becomes more unsettled next week as fast flow aloft with several weak impulses will traverse the region as low level moisture increases per easterly low level flow. In addition, some mid level monsoon moisture will advect into the region, helping to increase chances for showers and storms later in the week. Much cooler later in the week with widespread 70s for highs.

DISCUSSION

(This Evening Through Friday) Issued at 1232 PM MDT Fri Aug 7 2026

Current upper air models show mild ridge over the far western CONUS, with trough over the Great Lakes region, and northwest flow over the forecast area. Surface analysis depicts high pressure over the Dakotas, with a low over south central MT. Winds are relatively light and variable this afternoon. Skies are clear with temperatures currently in the 70s to low 80s.

Winds will slowly transition to out of the southeast as we progress through the afternoon, as the surface high slides east of the forecast area, with dry and mild conditions continuing the rest of today. Strengthening Low Level Jet tonight will increase chances for precipitation in the overnight hours, mainly over south-central SD. MU CAPE values in the 1500-2000 j/Kg range, along with steepening lapse rates and shear in the 35-45kt range will support chances for elevated strong storms with hail potential between around 09-14Z Saturday morning.

Hotter temperatures return for Saturday and Sunday, with highs in the 90s to possibly low 100s. Upper ridge flattens out a bit towards Sunday, bringing more quasi-zonal flow. Expect temperatures to cool a bit by Monday through the rest of next week. Low level southeasterly flow will be common next week, bringing increasing moisture into the region. Expect more active weather potential next week, with daily chances for at least isolated showers/storms

AVIATION

(For the 06Z TAFS Through 06Z Saturday Night) Issued At 956 PM MDT Fri Aug 7 2026

VFR conditions are expected through the TAF period. LLWS is likely southeast of the Black Hills after 08/06z (lasting through 08/12z), but should not affect the KRAP terminal. Smoke will increase over northeast Wyoming after 08/17z, potentially bringing a slight reduction to slantwise visibility for the KGCC terminal. Conditions will begin to improve by the end of the TAF period.

FIRE WEATHER

Issued At 938 PM MDT Fri Aug 7 2026

Very dry and breezy conditions expected this weekend. This will support red flag conditions across northeast WY and portions of northwest SD Saturday. Deep afternoon mixing behind a surface trough will allow wind gusts up to 35 mph with RH as low as 7 percent there. Elsewhere, near critical conditions can be expected across most of western SD as RH's drop to around 10 percent with a few gusts to around 25 mph. Widespread elevated conditions can be expected Sunday, with critical conditions possible across portions of northeast WY where breezy westerly winds are expected. The red flag warning may need to be extended through Sunday there. A cooling trend can be expected next week with unsettled conditions at times.

UNR WATCHES/WARNINGS/ADVISORIES

SD...Red Flag Warning from noon to 8 PM MDT Saturday for SDZ323-327. WY...Red Flag Warning from noon to 8 PM MDT Saturday for WYZ314>318.